1. Field of the Invention
The present invention relates to a novel chemical composition consisting of quantities of dry starting materials that can be added to water to generate chlorine dioxide [ClO2, Cl(IV) oxidation state] for cleaning, disinfection, sanitization, sterilization, and decontamination of surfaces contaminated with microorganisms or chemical agents without using exogenous power sources (e.g, electricity, open flames, chemical heat), large equipment or generators, or hazardous chemicals such as acids that are difficult to transport, store, handle, or dispose of. Chlorine dioxide is a broad-based biocide that is capable of inactivating a range of classes of contaminating microorganisms (e.g., bacteria, spores, viruses, fungi, protozoa, oocysts, etc.), is environmentally-friendly, and, because of its material compatibility, chlorine dioxide is also one of the safest and most effective decontamination and/or disinfectant methods available today. Chlorine dioxide is a well-known anti-microbial agent used in the decontamination community for its effectiveness against Anthrax (causative agent being spores of Bacillus anthracis) and harmful chemical agents. Chlorine dioxide, however, cannot be pre-generated then shipped or transported in trucks or other vehicles to distant locations for its application. For all its uses in decontamination, disinfection, sanitizing, and other purposes, chlorine dioxide must be generated in situ. The present invention provides in situ chlorine dioxide generation with on-site, at point-of-use, and at-will convenience.
The chlorine dioxide generated according to the instant patent application can be used for a wider variety of disinfecting, decontaminating, sanitizing, or sterilizing applications than previously possible anywhere microbial contamination may be an issue while overcoming drawbacks of the prior art and imparting several distinct technological advantages. For example, the chlorine dioxide can be used to decontaminate whole buildings or whole rooms, bio-safety cabinets in research or academic laboratories, hospital rooms, medical and dental facilities, textiles comprising clothing, shelters, and tents, bathrooms and shower facilities, kitchen and dining facilities, laundries, food handling equipment and contact surfaces in processing environments (including fresh produce), boat cabins or rooms in recreational vehicles, and in smaller spaces such as isolators, filtered housings, water purifiers, and laundries, and surfaces of personal use items such as boots and shoes, tools, cosmetic applicators, mouthwash, toothpastes, surgical and dental instruments, and drawing instruments, and contaminated objects in the interior chamber of a closable, vented container (e.g., Portable Chemical Sterilizer, U.S. Pat. No. 7,625,533) for sterilizing microbiologically contaminated surgical instruments, medical equipment, textiles, uniforms, fresh produce, or other contaminated surfaces. An embodiment of the invention also relates to the generation of chlorine dioxide solutions and chlorine dioxide gas for use in educational institutions, such as demonstrations, laboratory experiments, and directed research studies.
The use of the chemical composition of this invention for the generation of chlorine dioxide is particularly suited for military applications, especially in austere conditions restricting water consumption and electrical power demands and favoring lightweight transportability for rapid mobility such as in far-forward deployments, for decontaminating hard surfaces, textiles, shelters, deployable medical units, used surgical instruments, galleys, field kitchens and food service facilities, and laundries, bathrooms, showers, and latrines anywhere large numbers of personnel exist in a shared living environment. An embodiment of the invention empowers personnel with the germ-killing strength of chlorine dioxide, protects health and the environment, and unburdens individuals and the logistics chain through its lightweight design. Similarly, the chemical composition of this invention offers technological advantages that can be readily adapted for use in other types of austere environments such as occur in camping or remote or other outdoor activities, during disaster relief, and in the healthcare activities of less developed countries. The use of the chemical composition of this invention is particularly suited for civilian consumers for industry, retail, and household uses and can be readily adapted for these applications as a stand-alone disinfectant integrated with packaging technologies, or integrated into appliances, water purifiers, or other devices intended for household use.
Another embodiment of the invention is highly suited for educational purposes, in lecture and laboratory demonstrations, for example. In an embodiment of the invention, mixing small quantities of starting materials of a two-component chemical composition of dry reagents in water in a single-step mixing process, wherein the chlorine dioxide in solution is visible within seconds, to rapidly and controllably yield with increased user safety large volumes of dilute chlorine dioxide solutions from concentrations as low as 1-5 ppm to greater than 5000 ppm according to the user's desired concentration and intended purposes. This embodiment is simpler and more convenient in some situations, and it also retains its environmentally benign character as chlorine dioxide. This method can be exploited to develop a simple, safe method to demonstrate in a classroom or lecture hall setting the generation of chlorine dioxide, which can serve as an educational benefit not covered in the prior art.
2. Background of the Invention
Chlorine dioxide is well known for many years to be antiseptic and disinfecting. For its many applications in sanitizing, disinfecting, decontaminating, and sterilizing, chlorine dioxide concentrations are typically used in the ranges of 1-2 ppm, 5-25 ppm, 50-250 ppm, 1000-2500 ppm, or more, depending on the different needs of the individual applications and the desired physical state of chlorine dioxide needed for said applications. Chlorine dioxide is not transportable due to safety regulations, and so it cannot be pre-made then transported. For all its uses in decontamination, disinfection and sterilization purposes, chlorine dioxide must be generated in situ, on-site at point-of-use, and at-will. The need for the safe, environmentally benign generation of chlorine dioxide is not met by the prior art of conventional large-scale and small-scale chlorine dioxide generating equipment based on most oxidation-reduction reactions, electrochemical cells, or acidification. Thus, the prior art for generating chlorine dioxide can be organized into four categories: Oxidation-Reduction, Electrochemistry, Acidification, and Transient Intermediate Chemistry.
There are estimates that 4.5×106 lbs. of chlorine dioxide are used worldwide per day in far-reaching applications relating to paper and pulp mill industry, drinking water and wastewater treatment, food processing/foodservice, health, cooling towers, buildings (mold remediation or bio-threat decontamination), and anywhere microbial contamination is an issue. Because chlorine dioxide attacks lignin but not cellulose, its treatment of paper pulp leads to finished papers of a very desirable whiteness. It is estimated that the paper and pulp industries use as much as 10,000 lb. (4,500 kg) of chlorine dioxide per day to achieve these “bleaching” results. One technology to achieve this output is based on continuous reduction of sodium chlorate [ClO3−, Cl(V)] in high acid (H+) either in homogeneous chemical reactors or in electrochemical reactors. The acids used are hydrochloric acid (HCl, e.g., Day-Kesting Process) and sulfuric acid (H2SO4, e.g., Rapson Processes). Reductants include chloride [Cl−, Cl(—I)], sulfur(IV) (i.e., SO2), and methanol (Solvay Process). These processes are described in handbooks and encyclopedias of chemical technology; for example, in “Ullmann's Encyclopedia of Industrial Chemistry, 6th ed.,” which is hereby incorporated herein as a reference. Swindells et al. (U.S. Pat. No. 4,081,520) teach the refinement of the reduction of chlorate, wherein this process can be automated. Other technologies utilize the dichlorine [Cl2, Cl(0)] or hypochlorite [OCl−, Cl(I)] oxidation of chlorite [ClO2−, Cl(III)] to produce chlorine dioxide (ClO2). Beardwood teaches the further refinement of this art through automatic monitoring (U.S. Pat. No. 7,261,821 B2), and Martens et al. (U.S. Pat. No. 7,504,074 B2) teach programmable logic controllers and other changes to achieve responsive, fully automated control. While producing chlorine dioxide by the reduction of chlorate may be a process suitable in an industrial setting dedicated for that purpose, producing chlorine dioxide by chlorate reduction chemistry is technologically very undesirable and potentially hazardous, particularly in smaller, confined spaces such as kitchens, hospital rooms, rest rooms, class rooms, boats, or recreational vehicles, because all of the starting materials, unconsumed reactants, and byproducts (e.g., dichlorine for chlorate methods) are too dangerous, corrosive, or environmentally hazardous in such situations.
In the production of chlorine dioxide for potable water purification and wastewater disinfectant treatments, typical outputs in the amount of 220 lb. (100 kg) are produced per day and rely mainly on the oxidation of sodium chlorite (ClO2−) by dichlorine (Cl2). To perform this method of chlorine dioxide production, users commonly transport and bring to the treatment site pressurized cylinders of the dichlorine gas, which is a hazardous and combustible material. This method uses water as the medium to dissolve sodium chlorite, and teaches the flow of the dichlorine gas through this solution or passage of an electrical current through this solution to oxidize the chlorite ion [ClO2−, Cl(III)] to chlorine dioxide [ClO2, Cl(IV)]. Dichlorine itself is highly soluble in water. Upon dissolution it rapidly reacts with water to release hydrogen ion (H+), chloride ion (Cl−), and hypochlorous acid [HOCl, Cl(I)]. Hypochlorous acid dissociates into hydrogen ions (H+) and hypochlorite ions (OCl−). All four chemical species, the parent dichlorine and its three hydrolysis products, co-exist in rapid equilibrium, and the complete equilibrium description should, therefore, involve all of these species. To hasten the chlorite-dichlorine reaction, those skilled in the art of chlorine dioxide production may choose to add acid, usually hydrochloric (HCl), to the reaction mixture.
The production of chlorine dioxide [ClO2, Cl(IV)] from the two components chlorite [ClO2−, Cl(III)] and dichlorine [Cl2, Cl(0)] gas is exemplified in Jefferis, I I I et al. (U.S. Pat. No. 4,908,188). This patent teaches the necessity of preventing accidents and ensuring safety. It also recognizes the extreme corrosivity of dichlorine gas and its hydrolysis products, and, therefore, it teaches how to practice equipment redundancy (i.e., continued re-use of the generating apparatus), reliability and safety. The art further teaches controls, safety valves, and continuous monitoring of feedstock throughput and concentrations of chemical species. Problems inherent in the chlorite-dichlorine method of chlorine dioxide production include impurities in sodium chlorite that delay initiation of reaction with dichlorine, the presence of unreacted dichlorine in the output effluent gas, and the removal of chlorine dioxide after generation and use. These problems were overcome by Rosenblatt et al. (U.S. Pat. No. 5,234,678) by introducing carbon dioxide along with dichlorine to remove the sodium hydroxide impurity in sodium chlorite that delayed the production of chlorine dioxide; removing unreacted dichlorine gas by passage of the effluent gas through particulate soda-lime (comprised of calcium hydroxide, Ca(OH)2, water, H2O, sodium hydroxide, NaOH, and potassium hydroxide, KOH); and by removing residual chlorine dioxide by passage of used gas through a sodium thiosulfate (S2O32−) reductant solution. Clearly, this method is not suitable for on-site, energy-independent generation of chlorine dioxide for small-scale applications in confined spaces.
Sodium persulfate [S2O52−, S(VII)] is another specific chemical oxidant which has the requisite electrochemical potential to oxidize sodium chlorite [ClO2−, Cl(III)] to chlorine dioxide [ClO2, Cl(IV)]. Rosenblatt et al. teach the use of persulfate in the generation of chlorine dioxide gas for disinfection and decontamination (U.S. Pat. Nos. 4,504,442 and 4,681,739). This reaction is relatively slow, requiring 30-45 min at room temperature to produce the desired amount (approx. 11-113 ppm) of chlorine dioxide.
The oxidation of sodium chlorite [ClO2−, Cl(III)] to chlorine dioxide [ClO2, Cl(IV)] can be accomplished in an electrolysis cell. Tremblay et al. (U.S. Pat. No. 7,048,842 B2) teaches the use of a porous anode to accomplish this purpose electrochemically. Though the electrode processes have not been fully identified, passing an aqueous sodium chlorite feed solution through an electrolysis cell during the passage of electrical current converts a portion of the chlorite ion to chlorine dioxide. To improve conversion efficiency, the effluent solution can be recycled through the electrolysis cell. These additional steps are required to ensure the safety, redundancy, and efficiency of these electrochemical processes and also serve to illustrate the extra demands imposed for the continuous production of chlorine dioxide. The more numerous batch reaction methods for disinfection and decontamination of personal, medical, kitchen and recreational items and spaces with chlorine dioxide typically do not require such complex systems of powered equipment for production.
When generating chlorine dioxide in the form of dilute solutions or dilute gases or gas-phase mixtures, the acid-induced formation and disproportionation of chlorous acid [HClO2, Cl(III)] is commonly used. In the process of acidification, acid is added to a chlorite ion solution, whereupon chlorous acid forms and begins to disproportionate. Disproportionation itself is a complex form of oxidation-reduction reaction. Specifically, chlorous acid is thermodynamically unstable; it self-oxidizes and self-reduces to form more stable species. In this reaction, chlorous acid containing a chlorine atom of oxidation number+3 self-reacts to form a set of chlorine atom-containing products, some with higher oxidation numbers (+4, +5) and some with lower oxidations numbers (−1) than that of the chlorine atom initially in the disproportionating chlorous acid (+3). For the in situ generation of chlorine dioxide by acidification, an acid compound (usually a strong mineral acid) must accompany the chlorite during transportation, which creates the logistics burden of transporting hazardous materials (corrosive acids) that can endanger human health and are noxious to the environment. The resultant chlorine dioxide solution so produced is also acidic. These acidic materials require additional steps to ensure proper transportation, handling, storage, and safe disposal. Additionally, acid solutions can be corrosive to some surface materials, even while they are being disinfected by chlorine dioxide.
Where the oxidation of sodium chlorite by a particular oxidant requires specific constraints, conditions, and amounts characteristic of the chosen method, the acidification of sodium chlorite followed by disproportionation is decidedly different. It is an invariant process that always involves the same reaction, irrespective of the acidification agent. The stoichiometry and kinetics of this acidification reaction have been studied by many investigators; the contents of these published investigations are hereby incorporated herein into this application, particularly, “Kinetics and Mechanism of the Decomposition of Chlorous Acid,” J. Phys. Chem. A 2003, 107, 6966-6973, by A. K. Horváth, I. Nagypál, G. Peintler, I. R. Epstein, and K. Kustin, which summarizes the most recent and relevant of the previous studies. Since the acid dissociation constant chlorous acid is Ka≈1×10−2 M, or written as −log Ka=pKa≈2 (vide Horváth et al.), the goal of acidification is to raise the hydrogen ion (H+) concentration in the aqueous medium to a level where Cl(III) is present primarily or substantially as undissociated chlorous acid (HClO2) and not as dissociated chlorite ion (ClO2−). In actual practice, a person skilled in the art of chlorine dioxide production would add acid to lower the solution pH, preferably to a value in the vicinity of the chlorous acid pKa (i.e., so that pH≦pKa), and disproportionation becomes observable as the formation of chlorine dioxide.
It is known to those familiar with the art and science of chlorous acid disproportionation that in certain situations this disproportionation process is too slow to be of practical benefit. Three methods are used to speed up this reaction: increasing the hydrogen ion (H+) concentration, increasing the chloride ion (Cl−) concentration, and adding noble metal catalysts (Ostgard, U.S. Pat. No. 6,399,039). Strong mineral acid (primarily HCl or H2SO4) at concentrations 0.01 M or higher suffice to lower the pH to the point where disproportionation serves as a practical source of chlorine dioxide. At the later stages of the reaction, the chloride ion produced by the disproportionation reaction may reach a concentration sufficient to accelerate the reaction appreciably. Using hydrochloric acid to control the pH achieves the dual purpose of lowering the initial pH and accelerating the reaction by contributing chloride ions. When a weak acid such as citric acid is used as the hydrogen ion source, it is usually present in relatively large stoichiometric excess to provide sufficient acceleration to the reaction to be practical. Noble metal catalysts accelerate the chlorous acid disproportionation, but also add to the cost of chlorine dioxide production. To offset the increased cost, the catalyst can be recycled, but this process detracts significantly from the ease-of-use of the disproportionation method. It is further clear to those familiar with the art of chlorine dioxide production via acidification that the chlorous acid disproportionation reaction results in a spent solution too acidic, and therefore too hazardous, to be disposed down the drain, and requires additional steps not inherent in the production of chlorine dioxide, such as first raising the pH by neutralization, that compromise user-friendly convenience.
An early method for making chlorine dioxide on site through acidification was disclosed by Lovely (U.S. Pat. No. 3,591,515). The method taught by Lovely allows powdered sodium chlorite and a powdered proton source such as iron(III) chloride or citric acid to be mixed without reacting. These precursors are actually in the form of solutions adsorbed on solid substrates such as calcium silicate. Upon addition of water, protons are released and chlorine dioxide evolves. Such solid-state mixtures that release chlorine dioxide occur over time periods that are measured in weeks. Wellinghoff et al. (U.S. Pat. No. 5,705,092) teach sustained release of chlorine dioxide from multi-layered composites in which sodium chlorite is interspersed with dry acid-releasing agents. Upon exposure to water, acid is released and the chlorine dioxide evolves.
More copious release of chlorine dioxide by acidification is taught by Roensch et al. (U.S. Pat. No. 6,436,345 B1) in which the hydration of carbon dioxide serves as the proton source. Another method of allowing precursors to be in contact without reaction occurring is disclosed by Klatte (U.S. Pat. No. 6,635,230 B2), who teaches impregnation of zeolite crystals with sodium chlorite, such crystals mixed with proton generating substances. No reaction occurs until the water is added, whereupon chlorine dioxide is released.
It is well known in the chemical and chemical engineering arts that reactive precursors in solution can be segregated behind barriers such as valves or membranes prior to mixing. Roozdar (U.S. Pat. No. 5,407,656), for example, teaches the dissolution of reaction precursors in solution or in gel form in separate vessels. The solutions are then transported into a reaction chamber by opening of appropriate valves. To speed up the slow disproportionation reaction, and to make the rate of reaction more practical without using strong mineral acids, Roozdar teaches the addition of hydroxyl-free aldehydes such as glutaraldehyde to the reaction mixture. Dee et al. (U.S. Pat. No. 7,534,398 B2) teach the use of a membrane that dissolves when contacted by water to allow the segregated precursor solutions to react. Dee et al. teach a multi-compartmentalized apparatus for producing chlorine dioxide in aqueous solution, the gas phase, or as a mist for use in disinfecting personal or commercial items. An apparatus of Foster (US Patent Application 2005.0220666 A1) similarly teaches the use of chlorine dioxide among other “sterilants” for the purpose of disinfecting personal items, but does not specify how the chlorine dioxide is to be generated.
For certain applications such as treating industrial wastewaters or cleaning contact lenses, it may be necessary to remove or destroy chlorite from solution, and the disproportionation reaction finds use for this purpose. Kenjo et al. (EP No. 0196075 B1) disclose the cleaning of contact lenses by immersion of a soiled lens in an aqueous solution containing detergent and sodium chlorite in a patent marred by numerous ambiguities and errors. Following immersion, the cleaning solution with the soiled contact lens therein is boiled, for example, “ . . . at 1000 [sic] C. for 15 min.” The solution is cooled, whereupon any one of many named organic and inorganic acids may be added. It is clear from the context of this patent that this invention is not energy-independent and that the purpose of adding acid is acidification, to remove unreacted chlorite by forming the so-called and undefined species “free oxygen.” Simpson (U.S. Pat. No. 6,440,314 B1—vide for a critique of Kenjo et al.) teaches the addition of ascorbic acid or its diastereomer erythorbic acid to industrial wastewater to remove chlorite. Simpson teaches the addition of sufficient ascorbic acid so that its concentration exceeds that of the contaminating chlorite. For example, Simpson states his “ . . . invention employs approximately 5 ppm ascorbic acid to consume 1 ppm of chlorite ion.” Simpson further teaches that as a result of this treatment: “No chlorine dioxide is formed as long as ascorbic acid is in a slight excess.”
Industrial and municipal wastewater may contain contaminants that resist bacterial decomposition. Pre-treatment with strong and rapidly reacting oxidants can reduce the influence of contaminants such as surfactants and polyvinyl alcohols, and recondition the waste water for successful bacterial processing. Therefore, Tani et al. (Japanese Patent JP55035956) teach pre-treatment of wastewater with strong oxidants such as ozone or Fenton's reagent (hydrogen peroxide, H2O2, and an iron(II) salt). Cooper et al (U.S. Patent Application 2003/0203827) teach the addition of a mixture of chlorite and chlorate salts to wastewater, followed by acidification. Acidification forms chlorous acid, which disproportionates, releasing chlorine dioxide. The contaminated water so treated is allowed to circulate for several hours, thereby removing organic constituents and significantly reducing bacterial populations. This treatment should yield sufficiently decontaminated water that can be used for purposes such as cooling tower water.
Even the cleaning of surfaces such as those encountered in kitchens, bathrooms, shower, and laundry facilities can be rendered more efficient following pre-treatment with strong oxidants. Blagg et al. (International Patent Application WO03/062359 A1) teach the use of pH control to create a cleaning composition that is efficacious against contaminants that require either alkaline or acidic conditions for their removal. Coupled to the pH-elevating and pH-lowering components of the cleaner are reductants and oxidants. The addition of chlorite salts into the cleaner results in the production of chlorine dioxide during the pH-lowering phase of the cleaning, therefore, affording an antiseptic capability to this cleaner. Bianchetti et al. (U.S. Patent Application 2007/0214577 A1) teach the use of chlorite salts acidified, for example, with citric acid to pre-treat stains in fabrics prior to laundering, reportedly without harming the fabric.
It is understood that the generation of chlorine dioxide in the art prior to U.S. Pat. Nos. 7,625,533; 7,883,640; and 8,337,717 never teaches the reduction of chlorite; but rather, teaches only the oxidation of chlorite, the reduction of chlorate, or the disproportionation of chlorous acid formed by the acidification of chlorite, whose technological disadvantages and drawbacks the reduction of chlorite overcomes. As oxidation-reduction reactions involve electron transfer, it requires a fundamentally different type of chemical technology than occurs with the proton transfer inherent in acidification. As oxidation removes electrons and reduction contributes electrons, their fundamental difference in the direction of flow of matter render them distinct and separable chemical technologies, with no route obvious or otherwise, for transposing their fundamentally different character.
Doona et al. U.S. Pat. Nos. 7,625,533; 7,883,640; and 8,337,717 teach the generation of chlorine dioxide from chlorite by the reduction of chlorite using a novel electron-transfer effector in a chemical combination consisting of water, chlorite as oxidant, ascorbate ion as an electron-transfer chemical effector at sub-stoichiometric levels, sulfite as reductant, and iron-activated magnesium, with suitable permutations and substitutions possible for each chemical component comprising this system. The role of an electron-transfer chemical effector in the reduction process is critical: it initiates, speeds up, and alters the mechanism of the reaction between the oxidant and reductant leading to the controlled production of chlorine dioxide. The redox-active electron-transfer chemical effector interacts through fast (kinetically labile) redox reactions with chlorite to generate transient reactive intermediates, which induce the otherwise slow (kinetically inert) chlorite-reductant reaction to proceed according to alternative reaction pathways involving free radicals and electron-transfer and/or atom-transfer processes. In the absence of such an electron transfer chemical effector, the oxidant-reductant reaction is inert and does not proceed, particularly not on any practical timescale. The addition of a separate electron-transfer chemical effector thereby provides a combination that helps overcome the kinetic inertness of the otherwise thermodynamically-favorable, exothermic oxidant-reductant reaction, and controllably produces chlorine dioxide on a practical and relatively short timescale.
The generation of chlorine dioxide in the art of U.S. Pat. Nos. 7,625,533; 7,883,640; and 8,337,717 teach the use of an electron transfer chemical effector and the reduction of chlorite in the production of concentrated aqueous solutions of chlorine dioxide, whose concentrations are typically in the range of 500-5000 ppm or greater, including in the first stages of the art of Doona et al. U.S. Pat. No. 8,337,717, that involves the subsequent production of more dilute (>100 ppm chlorine dioxide) solutions. In fact, Doona et al. U.S. Pat. No. 8,337,717 requires a 2-step mixing process, wherein reagents are mixed in a small volume of solvent in Step 1 (called “pre-concentration”) to produce a concentrated solution of chlorine dioxide (1500-5200 ppm or greater), and the concentrated chlorine dioxide solution is diluted with solvent in Step 2 (called “post-reaction dilution”) by a factor of (26-106)-fold, resulting in an aqueous chlorine dioxide solution at its final working solution of >100 ppm. This 2-step mixing process is required to exert kinetics control over the chemical reaction processes to control the timescale of the reaction of 2-10 minutes and yield a relatively dilute (>100 ppm) chlorine dioxide solution. Adding all of the water (800 mL) initially to a composition (4.7 g chlorite, 1.3 g ascorbate, and 0.7 g sulfite) that produces >250 ppm chlorine dioxide when pre-concentrated in 15 mL results in reagent concentrations that are too dilute, such that the reaction effectively never takes place (0 ppm chlorine dioxide produced after 65 minutes), thereby being too slow for any practical utility.
With the aforementioned in view, it is clearly evident that until now there is presently no good, safe, rapid, and user-friendly method for rapidly and controllably producing dilute chlorine dioxide solutions involving the reduction of chlorite in a single-step mixing process for end-user convenience and ease-of-use for on-site, at-will, point-of-use, in situ production of chlorine dioxide. The present invention can rapidly produce aqueous chlorine dioxide solutions as dilute as 1-5 ppm with 1-step mixing, and thereby eliminates the need for the 2-step mixing process (exemplified in the art of Doona et al U.S. Pat. No. 8,337,717). The present invention rapidly produces chlorine dioxide solutions at concentrations of 1-10, 25-50, 50-100, or 100-250 ppm or greater. It is to be understood by practitioners familiar in the art that the present invention can also produce chlorine dioxide concentrations ≧500, 1500, 2500, 5000 ppm, or greater in the same 1-step process without changing the fundamental invention herein. The present invention also produces chlorine dioxide by combining only two chemical components in water, and therefore eliminates the need for an electron transfer chemical effector to initiate chemical reaction, thereby providing a distinct advantage over prior art, including the aforementioned art embodied in U.S. Pat. Nos. 8,337,717; 7,625,533; and 7,883,640.